Animal Molecular Breeding, 2013, Vol.3, No.2, 4
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are many source of information, which can provide
clues about an individual’s breeding value. These
include individual performance, family performance
and combined performance of individual and family
weighted appropriately (Dalton, 1985; Nicholas, 1987;
Falconer, 1989) after correction for known environment
effects. The Conditions under which the use of these
different sources of information are appropriate and
well documented in the literature (Falconer, 1989;
Micholas, 1993). A point worth highlighting is that
when heritability is low, combining individual and family
performances, appropriately weighted, provides the
maximum response to selection (Falconer, 1989). This
is because the estimated breeding value of an
individual using data from different relationships is
more accurate than a single estimate from the
individual alone (Falconer, 1989; Micholas, 1989).
In practical animal breeding, multiple traits are usually
measured on each individual to collect as much
information as possible about its productivity. In
genetic studies, multivariate estimation of (Co)
variance components and genetic values for sire
evaluation has recently been received considerable
attention. In most of the cases, the breeding values of
sires have been estimated using single trait models.
However, now-a-days, there is a constant thrust to get
best linear unbiased prediction (BLUP) evaluations
using a single or multitrait animal model.
As per objectives under the present study the sires
have been ranked on the basis of solution obtained
through univariate and multivariate REML using
animal model and BLUP value for sire effects under
model 8 and find out rank correlations among
sires/animals on the basis of BLUP values.
1
Results and Discussion
The phenotypic mean (±S.E.) of body weights at birth,
weaning and 6 month of age were (2.84±0.50) kg,
(11.65
±2.84) kg and (16.72±3.59) kg, respectively and
first greasy fleece yield clipped at the age of 6 month
was (0.95±0.33) kg. Phenotypic range of data were
1.00
kg to 4.50 kg for body weight at birth, 4.40 kg to
21.20
kg for weaning weight, 6.40 kg to 30.00 kg for
6
month body weight and 0.14 kg to 2.40 kg for first
greasy fleece yield with corresponding standardized
range of -3.17 to 3.36, -2.56 to 3.37, -2.88 to 3.70 and
-2.49
to 4.45 respectively (Table 1). On standardized
scale body weight had shown more variation than
other traits, because at this stage culling by natural
means may not take place. After that the standardized
range has reduced at WWT and then almost stabilized.
It appears reasonable that the weights become mort
uniform after the maternal influence and weaning
weight stress have passed (Bhathaci and Leroy, 1998).
Table 1 Phenotypic mean (X), Standard deviation (S.D.), Phenotypic standard deviation (6
p
),
Phenotypic range (Pr) and Standardized
range (Sr) of data
Parameter
Traits
Birth weight
Weaning weight
6
month weight
First Greasy Fleece yield
X
2.84
11.65
16.72
0.95
S.D.
0.50
2.84
3.59
0.33
6
P
0.48
2.44
3.03
0.29
Pr
Min.
1.00
4.40
6.40
0.14
Max.
4.50
21.20
30.00
2.40
Sr
Min.
-3.71
-2.56
-2.88
-2.49
Max.
3.36
3.37
3.70
4.45
Under normal curve, 17.47% population falls on mean
for BWT, where as the corresponding values for weaning
weight, weight at 6 month and first greasy fleece yield
wee, 24.36%, 21.45% and 34.31% respectively. The
phenotypic standard deviation under univariate analysis
were 0.477, 2.443, 3.029 and 0.288 respectively for
BWT, WWT, 6WT and GFYI.
The least squares mean (±S.E.) estimated by model 2
and model 8 for birth weight, weaning weight, weight
at 6 month and first greasy fleece yield different traits, are
presented in Table 2. The means estimated by model 8
were slightly different from the means estimated by
model 2. Kushwaha (1994), Kushwaha et al. (1997)
and Anonmous (1998) reported similar birth weight in